Malicious PDF — malware analysis report

Static analysis result for SHA-256 3cef37c03da75a6f…

MALICIOUS

PDF

74.1 KB Created: 2021-07-06 04:48:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 64dccd53981b7401d73a3e4b0687a1ce SHA-1: 5ee018fd16396c96222f9c3e59fa951b98f3d484 SHA-256: 3cef37c03da75a6f1259a8a0b205fc514316783ab8d7952c858f7bacd8e6ccf6
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised WordPress sites and disposable hosting, forming a link farm. This suggests the document's primary purpose is to lure users into clicking these links, likely leading to further malicious content or phishing attempts. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/dpm3bg7e2jbb9h5b7cm99nh7v1/tuwojat.pdf In PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a670255cab4---zoziralovataremelevom.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607ed3e10e086---lunuziderofojukabimef.pdfIn PDF document text
    • http://chickenwild.com/upload/contents/images/images/buvitexudemuxivozoludapuv.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/160913f7b00ae5---roxukurokamebijinidopepow.pdfIn PDF document text
    • https://asi-filter.pl/files/file/natitiw.pdfIn PDF document text
    • https://lescourailleurs.com/upload/editor/file/buxuk.pdfIn PDF document text
    • http://c2ctrading.org/cms_upload/files/bosesufekadowajujo.pdfIn PDF document text
    • https://ecobox.eng.br/wp-content/plugins/super-forms/uploads/php/files/b97ikkuesdche2ak15ot1at1uj/moxaremowafapilejesu.pdfIn PDF document text
    • http://sgyscom.com/upload_fck/file/2021-6-29/20210629063300953186.pdfIn PDF document text
    • http://balone.net/_upload/file///borir.pdfIn PDF document text
    • https://fenixfalt.com/userfiles/file/89682058992.pdfIn PDF document text
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/5p2j7kot6lbl2l2r6h46qqug5e/26221926183.pdfIn PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a66cf1d885a---30111605389.pdfIn PDF document text
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160871c96cfb56---rifavokajezelaneno.pdfIn PDF document text
    • http://zaun-produzent.de/userfiles/file/24372369669.pdfIn PDF document text
    • http://sanitaerprofi.ch/fckeditor/editor/images/file/6749810933.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/s67o8rsvoh2prr5a23cl3t0qq2/72585785674.pdfIn PDF document text
    • http://sanders-scottfamily.com/clients/26926/File/xigelumilimazikozopabex.pdfIn PDF document text
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/bq7c9hjli3dim0is7uck630bv1/2649454884.pdfIn PDF document text
    • http://ldbell1965.net/clients/85689/File/tozagivirunevekikexo.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce5ee1dc56---66929324859.pdfIn PDF document text
    • http://eldmsh1.ru/js/ckfinder/userfiles/files/nobetapixosibojuwilow.pdfIn PDF document text
    • http://elcampoeco.org/FCKeditor/file/84987234338.pdfIn PDF document text
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074409cec5fc---19700666510.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=solubility+of+organic+compounds+pdfPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c0ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0FF 11260 bytes
SHA-256: 6b1c9b1682dfc17e3b4dcb368f6b0cb47244567e7876b2bfe0fd566f9d83876d
font_01_sfnt_off0000dafc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAFC 15680 bytes
SHA-256: 430650746c166451ae01a4360c2ecc223f37f70b7be0c8fa41df0cc80a50c763
font_02_sfnt_off00010332.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10332 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1